25pts求条

#include<bits/stdc++.h>
using namespace std;
int n,m;
const int MAXN=205;
const int MAXM=6005;
struct Edge{
	int u,v,w;
}edge[MAXM];
int fa[MAXN];
int vis[MAXN];
int find(int x){
	if(fa[x]==x)return x;
	return fa[x]=find(fa[x]);
}
bool cmp(Edge a,Edge b){
	return a.w<b.w;
}
int kruskal(){
	int ans=0;int cnt=0;
	for(int i=1;i<=n;i++)fa[i]=i;
	sort(edge+1,edge+m+1,cmp);
	for(int i=1;i<=m;i++){
		int fu=find(edge[i].u);
		int fv=find(edge[i].v);
		if(fu!=fv){fa[fu]=fv;ans+=edge[i].w;cnt++;}
		if(cnt==n-1)return ans;
	}
	return -1;
}
int main(){
	cin>>n>>m;
	for(int i=1;i<=m;i++){
		cin>>edge[i].u>>edge[i].v>>edge[i].w;
		if(i<n-1){
			cout<<-1<<endl;
			continue;
		}
		cout<<kruskal()<<endl;
	}
	return 0;
}